Scientists said on Sunday that they can no longer rule out ‘a fast-track melting of the Greenland icesheet — a prospect, once the preserve of doomsayers, that would see much of the world’s coastline drowned by rising seas.‘

The researchers found that the great Laurentide icesheet which smothered much of North America during the last Ice Age melted far swifter than realised, dumping billions of tonnes of water into the ocean.

The discovery raises worrying questions about the future stability of Greenland’s icesheet, for the Laurentide melt occurred thanks to a spurt of warming that could be mirrored once more by the end of this century, they said.

“The word ‘glacial’ used to imply that something was very slow,” said climate researcher Allegra LeGrande of New York’s Columbia University.

“This new evidence from the past, paired with our model for predicting future climate, indicates that ‘glacial’ is anything but slow. Past icesheets responded quickly to a changing climate, hinting at the potential for a similar response in the future.”

The research of the scientists was published online by the journal Nature Geoscience.

In a commentary, also published in Nature Geoscience, Earth scientists Mark Siddall and Michael Kaplan said Greenland’s glacial slab was entering into a temperature range at which it was becoming “particularly vulnerable.”

“[The new] work suggests that future reductions of the Greenland ice sheet on the order of one metre (3.25 feet) per century are not out of the question,” they said.

It will be interesting to see the reaction of other scientists to this research. Keeping an eye on it.